Applications
Reagent for the detection of histidine; intermediate for dyes and pharmaceuticalsSulfanilic acid is used as a reagent for chromatographic detection of histidine. It is also used as a chemical intermediate in organic synthesis. It is utilized in quantitative analysis of nitrate and nitrite ions. It plays an essential role in the manufacturing of azo dyes and in synthesis of sulfa drugs. It is used as a dopant for the chemical synthesis of polyaniline. It is used to prepare 2,4-diamino-6-p-sulphoanilinopyrimidine by reacting with 6-chloro-pyrimidine-2,4-diamine.

Solubility
Slightly soluble in water. Insoluble in ethanol, ether, caustic soda and sodium carbonate.

Notes
Incompatible with strong oxidizing agents, strong acids and strong bases.